Officials say that more than a dozen classified rulings have created a secret body of law that gives the NSA the power to gather massive information collections on Americans. The data collection is not just restricted to terrorism suspects but "people possibly involved in nuclear proliferation, espionage and cyberattacks."

According to officials who are familiar with these classified rulings, the court has expanded it's role while assessing "broad constitutional questions" and establishing judicial precedents without any public scrutiny. Some rulings are over 100 pages long.

The role of the FISA court has changed over the years, originally approving case by case wiretaps. In 2007, with greater judicial oversight of intelligence operations and other legislation, the FISA court "has quietly become almost a parallel Supreme Court, serving as the ultimate arbiter on surveillance issues and delivering opinions that will most likely shape intelligence practices for years to come, the officials said."...